The Maryland Department to of Health and Mental Hygiene (DHMD), AIDS Administration is requesting $1,417,943 over three years from the U.S. Department of Health and Human Services, Centers for Disease Control and Prevention (CDC) to implement the National HIV Behavioral Surveillance System (NHBS) in the Baltimore, Maryland metropolitan area. The NHBS is an anonymous research study which focuses on recruiting three populations at risk for HIV infection: Men who have sex with men (MSM), injection drug users (IDU), and heterosexuals at increased risk for HIV infection (HET). This study will consist of a series of three cross-sectional surveys using the same interview instrument, which will recruit each of the above risk populations. MSM recruitment will be completed by December 2008, IDU recruitment by December 2009, and HET recruitment by December 2010. The proposed sample size for each of the target population is a minimum of 500 participants. The proposed study will include a detailed questionnaire to gather information on demographics, sexual and drug use behaviors, HIV testing, and utilization of local HIV prevention program services. The questionnaire will be standardized nationally, with the addition of a limited number of questions specific to Baltimore. The study will also offer HIV testing, utilizing both FDA approved HIV diagnostic tests and the Serologic Testing Algorithm for Recent HIV Seroconversion (STARHS) for the identification of recent infections. The sampling and recruitment methodologies will be selected as appropriate for each of the target populations (MSM, IDU, and HET) and will be developed in collaboration with the CDC. MSM recruitment will be venue-based. Public venues (e.g., bars, clubs, etc) in Baltimore City will be randomly sampled and eligible men will be requested to consent to a blood draw and a questionnaire. IDU recruitment will utilize respondent driven sampling (RDS). Initial IDU participants will be recruited through key community informants and after consenting to a blood draw and a questionnaire will then be trained to recruit additional IDUs. Successive waves of IDU recruits will recruit additional IDUs. Successive waves of IDU recruits will recruit additional IDUs. HET recruitment will be either through venue-based recruitment, as with MSM, or respondent driven sampling, as with IDUs, and will be selected in collaboration with the CDC. The NHBS activities in the Baltimore metropolitan area will produce valuable information for measuring HIV risk behaviors and for planning and targeting HIV prevention activities in Maryland. The CDC has proposed performing NHBS in 25 high HIV prevalence metropolitan areas nationwide, and the combined data will produce national estimates of HIV risk behaviors in high-risk populations in the most affected regions of the country. [unreadable] [unreadable] [unreadable]